Organic light emitting element, display apparatus, image pickup apparatus, and illumination apparatus

Patent metadata

Field	Value
Publication number	US-10840470-B2
Application number	US-201916368675-A
Country	US
Kind code	B2
Filing date	Mar 28, 2019
Priority date	Mar 30, 2018
Publication date	Nov 17, 2020
Grant date	Nov 17, 2020

Abstract

One embodiment of this invention has a first electrode, a first light emitting layer, and a second electrode, in which the first light emitting layer has a first host material and a first dopant material, a lowest triplet excitation energy of the first host material is higher than a lowest triplet excitation energy of the first dopant material, and, when a weight of the first light emitting layer is set to 100 wt %, a concentration of the first dopant material is 0.3 wt % or less.

First claim

What is claimed is:

1. An organic light emitting element comprising:
a first electrode;
a first light emitting layer;
a second light emitting layer; and
a second electrode, in this order,
wherein:
the first light emitting layer includes a first host material and a first dopant material,
the second light emitting layer includes a second host material and a second dopant material;
a lowest triplet excitation energy of the first host material is higher than a lowest triplet excitation energy of the first dopant material,
an energy gap of the second dopant material is larger than an energy gap of the first dopant material, and
when a weight sum of the first host material and the first dopant material is set to 100 wt %, a concentration of the first dopant material is 0.3 wt % or less.

2. The organic light emitting element according to claim 1 , wherein
the first dopant material is a fluorescent light emitting material.

3. The organic light emitting element according to claim 1 , wherein
a difference between the lowest triplet excitation energy of the first host material and the lowest triplet excitation energy of the first dopant material is 0.3 eV or less.

4. The organic light emitting element according to claim 1 , wherein
a lowest triplet excitation energy of a first organic compound layer contained in a region from the first light emitting layer to the second light emitting layer is equal to or less than a lowest triplet excitation energy of a second organic compound layer adjacent on a side of the second electrode to the first organic compound layer.

5. The organic light emitting element according to claim 1 , wherein
a lowest triplet excitation energy of the second host material is higher than the lowest triplet excitation energy of the first host material.

6. The organic light emitting element according to claim 1 , wherein
a lowest triplet excitation energy of the second host material is lower than a lowest triplet excitation energy of the second dopant material.

7. The organic light emitting element according to claim 1 , wherein
in a material contained in the first light emitting layer and a material contained in the second light emitting layer, a difference between a lowest singlet excitation energy and a lowest triplet excitation energy is 0.2 eV or more.

8. The organic light emitting element according to claim 1 , wherein
the first host material and the second host material are identical.

9. The organic light emitting element according to claim 1 , wherein
the first light emitting layer and the second light emitting layer are in contact with each other.

10. The organic light emitting element according to claim 1 further comprising:
an intermediate layer disposed between the first light emitting layer and the second light emitting layer, wherein
a lowest triplet excitation energy T1(HM) of the intermediate layer is equal to or less than a lowest triplet excitation energy of the second host material and equal to or more than the lowest triplet excitation energy of the first host material.

11. The organic light emitting element according to claim 1 , wherein
the first light emitting layer and the second light emitting layer are light emitting layers emitting white color by the first light emitting layer and the second light emitting layer, and
the organic light emitting element has a color filter on a light emitting side.

12. The organic light emitting element according to claim 1 , wherein
the first light emitting layer further includes a third dopant material, and
a lowest triplet excitation energy T1(H1) of the first host material and a lowest triplet excitation energy T1(D3) of the third dopant material satisfy the following expression (4),
0 eV< T 1( H 1)− T 1( D 3)<0.3 eV  (4).

13. The organic light emitting element according to claim 1 , wherein
when the weight sum of the first host material and the first dopant material is set to 100 wt %, a weight ratio of the first dopant material is 0.05 wt % or more and 0.3 wt % or less.

14. The organic light emitting element according to claim 1 , wherein
the first host material is a low molecular organic compound.

15. A display apparatus comprising:
a plurality of pixels, wherein
each of the pixels includes the organic light emitting element according to claim 1 and an active element connected to the organic light emitting element.

16. An image pickup apparatus comprising:
an optical section having a plurality of lenses;
an image pickup element receiving light passing through the optical section; and
a display section displaying an image, wherein
the display section is a display section displaying an image picked up by the image pickup element, and
the display section includes the organic light emitting element according to claim 1 .

17. Electronic equipment comprising:
a display section including the organic light emitting element according to claim 1 ;
a housing in which the display section is provided; and

a communication section provided in the housing.

18. An illumination apparatus comprising:
a light source including the organic light emitting element according to claim 1 ; and
a light diffusion section or an optical film transmitting light emitting by the light source.

19. A moving body comprising:
a lighting tool including the organic light emitting element according to claim 1 , and
a body in which the lighting tool is provided.

20. The organic light emitting element according to claim 1 ,
wherein the first dopant material is a light emitting material and the second dopant material is a light emitting material;
and wherein an emission wavelength of the first dopant material is longer than an emission wavelength of the second dopant material.

Assignees

• Canon Kk

Inventors

• Takahashi Tetsuo
• Shiobara Satoru
• Ishige Koichi
• Yamaguchi Tomona
• Ishizuya Koji
• Ito Takayuki
• Kajimoto Norifumi

Classifications

• H04N23/63

  by using electronic viewfinders · CPC title

• H10K2101/20

  Delayed fluorescence emission · CPC title

• H10K2101/40

  Interrelation of parameters between multiple constituent active layers or sublayers, e.g. HOMO values in adjacent layers · CPC title

• H04N23/54

  Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils · CPC title

• H04N23/53

  of electronic viewfinders, e.g. rotatable or detachable · CPC title